The chickenpox vaccine may work for adults, but only for people who have not had chickenpox before and have not had the chickenpox vaccine. If you have had chickenpox or the chickenpox vaccine before, your body has probably developed the appropriate antibodies to chickenpox, so there is no need to get the chickenpox vaccine at this time. The reason is that the chickenpox vaccine is also designed to allow the body to produce the appropriate antibodies and gain immunity to chickenpox. Only if the adult has never had chickenpox before and has not had the chickenpox vaccine, then the chickenpox vaccine may work. It is also recommended that two doses of chickenpox vaccine be given at intervals so that the adult can gain immunity to chickenpox. If a child gets chicken pox, the clinical symptoms may not be serious, but if an adult or an elderly person gets chicken pox at that age, the symptoms may be serious. So for adults who do not have the appropriate immunity, the chickenpox vaccine can be beneficial.